Definition: 'Paragonimus Westermani'

Paragonimus westermani

Type: Term

Definitions:
1. the bronchial or lung fluke; a species that causes paragonimiasis, found chiefly in Japan, Korea, Taiwan, China, the Philippines, and Thailand; eggs are coughed up in sputum or swallowed and passed in the feces; miracidia invade Melania snails, and produce large numbers of stumpy-tailed cercariae that leave the snail and crawl into muscles and viscera of crayfish or crabs and encyst; in humans the excysted worms invade the wall of the gut and migrate through the diaphragm into the lungs; the developing parasites cause an intense inflammatory reaction and eventually induce fibrous-walled nodules that usually contain a pair of adult worms, along with exudate, eggs, and remains of red blood cells; the fibroparasitic nodules may become contiguous and form multiloculated cystlike structures; in some instances, the flukes involve the brain, liver, peritoneum, intestine, or skin.